• Bring a jacket, since the chambers stay chilly and close to 100% humid even on hot summer days
• No strollers or toilets inside: park the stroller at the glass entrance pyramid, and the nearest toilet is in the orange house in Søndermarken, about 200 meters away
• Dark and echoey chambers with a 17-second reverb, so kids need to walk slowly, talk softly and keep their hands off the stalactites

Cisternerne is a former drinking-water reservoir under Søndermarken park, built in 1856-59: three dark, granite-walled chambers with stalactites growing from the concrete ceiling. Each year an international artist makes a show for the space, so the visit changes every year.

The 2026 show, Marina Abramović's Seven Deaths, is about an hour of opera films that stage seven deaths. It suits curious, calm kids who are fine in the dark.